Rates of women who are opting for preventive mastectomies, such as Angeline Jolie, have increased by an estimated 50 percent in recent years, experts say. But many doctors are puzzled because the operation doesn't carry a 100 percent guarantee, it's major surgery -- and women have other options, from a once-a-day pill to careful monitoring.

"Allah used Muslim scientists to expose the Western plot of using polio vaccines to reduce our population," said the 28-year-old Muslim food vendor in Kano.

Each time health teams have tried to vaccinate her daughter, Garba has refused.

It's been three years since local politicians began a campaign of fear and rumor, claiming the polio vaccine would sterilize children. Those unfounded fears still persist today, and it's this myth, and others like it, that are largely responsible for the spread of polio into almost two dozen other countries where it was once stamped out.

"The world is still paying the price for what happened in Nigeria in 2003," said Dr. David Heymann, the top official for polio eradication with the World Health Organization. Most of the new infections in other countries can be traced to Nigeria.

WHO and its partners had to give up their goal of eradicating polio globally by 2005. Responding to the cascade of outbreaks caused by Nigeria cost an extra $200 million last year alone, said Heymann.

Fears about the polio vaccine have been so prevalent in rural Nigeria that villagers have fled their homes when polio vaccinators arrive.

Rising cases of polio
In 2003, vaccinations were suspended in Nigeria for nearly a year while tests were done to convince local officials that the vaccine was not contaminated with estrogen. Anti-fertility agents were never detected.

So the politicians lifted their ban, and the governor of Kano had his daughter publicly vaccinated. But some leaders never fully endorsed the vaccine, and distrust persists in many parts of the country. The number of polio cases in Nigeria continues to rise. There were 355 cases in 2003; so far in 2006, there are more than 800 cases, WHO reports.

Vaccine fears are nothing new. Rumors about the dangers of vaccines date back to the 18th century when the world's first vaccine, for smallpox, was created. Vaccines are frequently credited with saving millions of lives worldwide, but they are still perceived by some as a dangerous medical gamble.

Part of the problem in Nigeria and some other developing nations, experts say, is rooted in health workers' own failure to be honest with people in poor countries about real vaccine-related risks.

Not telling real vaccination risks
Health officials have often kept quiet about the one obvious adverse effect the polio vaccine can cause: polio. For roughly every 3 million doses of the oral vaccine given, one child is paralyzed by the live virus in the vaccine itself.

In the developed world, it is virtually a legal requirement to inform people of any potential vaccine-associated risks. But in the developing world, standards of informed consent are often abandoned as a logistical stumbling block.

Some medical ethicists say this failure to educate is wrong — regardless of the difficulties in the field.

"Failing to divulge adverse effects is non-transparent, and it's essentially a lie," said Dr. Ross Upshur, a medical ethics specialist at the University of Toronto. "There's no point in controlling infectious diseases if you've violated communities' dignities and rights in the process."

Claire Hajaj, who has worked on polio eradication at UNICEF, said communicating medical risk to illiterate and remote populations isn't always possible. "Usually, you have to settle for something that's not quite as perfect," Hajaj said.

In impoverished regions struggling with a variety of deadly epidemics, it's often difficult even to make people understand the value of polio vaccination.

"We go repeatedly to families who have no electricity or sanitation," said Michael Galway, head of UNICEF's polio communications in India. "They see their kids dying from things like malaria and diarrhea. And then we bring the polio vaccine — which is not what they want."

Though public health officials are making headway in convincing local populations that vaccines save lives, the battle remains. In Nigeria, some mothers try to fool health workers into believing their children have been vaccinated by painting their children's fingers with nail polish, an attempt to imitate the ink marks used in vaccine drives to record that a child has been immunized.

Some vaccinators chased out
In Pakistan, a recent court petition — citing Nigerian documents that claim the vaccine contains estrogen — asks the government to end the polio eradication program. In the past, polio vaccinators in Quetta have been stoned and chased out by angry locals.

And in Kenya, there have been devil worship allegations: Parents feared that having their children take the oral vaccine would result in their tongues being magically removed.

Vaccination fears can arise in wealthy nations, too. In Britain, debate raged for years over the safety of the measles, mumps and rubella vaccine after flawed research in 1998 suggested it was connected to a rise in autism cases. Many other studies found no connection, and most of the scientists involved in the discredited 1998 report retracted it.

Still, there is a lingering credibility problem. "Governments are not trusted as a source of medical information," said Dr. David Salisbury, head of immunization for Britain's department of health.

And it is difficult to quell vaccination rumors once they start. In Nigeria, experts thought the polio vaccine issue was resolved when politicians lifted the vaccine ban in July 2004.

But for Nigerians like Sadiya Musa, the flip-flop causes even more suspicion.

"How can they say the vaccine is bad and then say it is good again?" asked the mother of six, who believes the vaccine causes sterility and HIV/AIDS. "I cannot be deceived."

Copyright 2006 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.